The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 2019
Filed:
Dec. 28, 2012
Axcelis Technologies, Inc., Beverly, MA (US);
Edward K. McIntyre, Franklin, MA (US);
Edward J. Ladny, Lynn, MA (US);
Nathaniel Robinson, Eliot, ME (US);
William Davis Lee, Newburyport, MA (US);
Axcelis Technologies, Inc., Beverly, MA (US);
Abstract
An electrostatic clamp monitoring system has an electrostatic clamp configured to selectively electrostatically clamp a workpiece to a clamping surface via one or more electrodes. A power supply electrically coupled to the electrostatic clamp is configured to selectively supply a clamping voltage to the one or more electrodes. A data acquisition system is coupled to the power supply and configured to measure a current supplied to the one or more electrodes, therein defining a measured current. A controller integrates the measured current over time, therein determining a charge value associated a clamping force between the workpiece and electrostatic clamp. A memory stores the charge value associated with the clamping force over a plurality of clamping cycles, therein defining a plurality of charge values, and the controller determines a clamping capability of the electrostatic clamp based on a comparison of a currently determined charge value to the plurality of charge values.